The present disclosure generally relates to a gas range system, and more particularly to an improved exhaust vent system for a gas oven.
Conventional gas operated cooking appliances such as gas ovens, for example, have one or more burners in which gas is mixed with air and burned. These types of ovens are heated by burning gas, either natural gas or vaporized liquid petroleum gas. Fresh air is drawn in through burner units that mix the gas with the air for combustion. The gaseous products of combustion must be discharged or otherwise escape from the oven cavity.
Typically, a gas oven will include a gas burner located in the bottom portion of the oven that is used for general baking and cooking. This burner will generally be referred to as a bake burner. The gas oven can also include a gas burner at the top of the oven, which is generally referred to as a broil burner. Both the bake burner and the broil burners are generally open flame types of gas burners.
During heating of the gas oven, there is a continual supply of gas and air that is combusted. The gaseous products of combustion are normally vented to the atmosphere. For example, some gas ovens include a venting system that vents the gaseous products through a vent in the upper rear portion of the oven cavity that extends through the upper wall or rear wall of the oven and into the kitchen or out through a duct.
Generally, a worst case condition for clean combustion in a gas oven having both a bake burner and a broil burner is during the broil mode. As the broil burner is located near the top of the oven cavity, there is less stack height to develop and drive air flow through the oven cavity and into the vent. Another worst case condition for a gas oven is when the gas oven is cold and first activated. Due to the cool initial temperature in the interior of the oven, stack pressure sufficient to drive air flow through the oven cavity builds slowly during the warm-up period. Also, other variables such as quenching of cold surfaces on the burner flames can result in higher amounts of emissions during the warm-up period.
To compensate for the reduced stack height for the broil burner or the reduced stack pressure during the warm-up period of the gas oven, the exhaust vent cross-sectional area will typically be oversized. In some cases, the vents can be at least twice the size they need to be for most usage. Although a larger vent size may improve combustion for broil and warm-up conditions, the larger vent size also means that for the other operating conditions, the oven will not be as efficient as it could be with a smaller vent. Also, an oversized vent can allow excess heat to vent out of the oven. Thus, a one-size vent cannot provide optimum performance for all of the operating conditions of the oven.
Accordingly, it would be desirable to provide a system that addresses at least some of the problems identified above.